A computerized axial tomography scan (commonly known as a CAT scan or a CT scan) is an x-ray procedure, which combines many x-ray images with the aid of a computer to generate cross-sectional views of the internal organs and structures of the body. In each of these views, the body image is seen as an x-ray “slice” of the body. Typically, parallel slices are taken at different levels of the body, i.e., at different axial (z-axis) positions. This recorded image is called a tomogram, and “computerized axial tomography” refers to the recorded tomogram “sections” at different axial levels of the body. In multislice CT, a two-dimensional (2D) array of detector elements replaces the linear array of detectors used in conventional CT scanners. The 2D detector array permits the CT scanner to simultaneously obtain tomographic data at different slice locations and greatly increases the speed of CT image acquisition. Multislice CT facilitates a wide range of clinical applications, including three-dimensional (3D) imaging, with a capability for scanning large longitudinal volumes with high z-axis resolution.
Magnetic resonance imaging (MRI) is another method of obtaining images of the interior of objects, especially the human body. More specifically, MRI is a non-invasive, non-x-ray diagnostic technique employing radio-frequency waves and intense magnetic fields to excite molecules in the object under evaluation. Like a CAT scan, MRI provides computer-generated image “slices” of the body's internal tissues and organs. As with CAT scans, MRI facilitates a wide range of clinical applications, including 3D imaging, and provides large amounts of data by scanning large volumes with high resolution.
Medical image data, which are collected with medical imaging devices, such as X-ray devices, MRI devices, Ultrasound devices, Positron Emission Tomography (PET) devices or CT devices in the diagnostic imaging departments of medical institutions, are used for an image interpretation process called “reading” or “diagnostic reading.” After an image interpretation report is generated from the medical image data, the image interpretation report, possibly accompanied by representative images or representations of the examination, are sent to the requesting physicians. Today, these image interpretation reports are usually digitized, stored, managed and distributed in plain text in a Radiology Information System (RIS) with accompanying representative images and the original examination stored in a Picture Archiving Communication System (PACS) which is often integrated with the RIS.
Typically, prior to the interpretation or reading, medical images may be processed or rendered using a variety of imaging processing or rendering techniques. Recent developments in multi-detector computed tomography (MDCT) scanners and other scanning modalities provide higher spatial and temporal resolutions than the previous-generation scanners.
Advanced image processing was first performed using computer workstations. However, there are several limitations to a workstation-based advanced image processing system. The hardware and software involved with these systems are expensive, and require complicated and time consuming installations. Because the workstation can only reside in one location, users must physically go to the workstation to use the advanced image processing software and tools. Also, only one person can use the workstation at a time.
Some have improved on this system by converting the workstation-based advanced image processing system to a client-server-based system. These systems offer some improvements over the workstation-based systems in that a user can use the client remotely, meaning the user does not have to be physically located near the server, but can use his/her laptop or computer elsewhere to use the software and tools for advanced image processing. Also, more than one client can be used with a given server at one time. This means that more than one user can simultaneously and remotely use the software that is installed on one server. The computational power of the software in a client-server-based system is distributed between the server and the client. In a “thin client” system, the majority of the computational capabilities exist at the server. In a “thick client” system, more of the computational capabilities, and possibly data, exist on the client.
The hardware software installation and maintenance costs and complexity of a client-server based system are still drawbacks. Also, there can be limitations on the number of simultaneous users that can be accommodated. Hardware and software must still be installed and maintained. Generally the information technology (IT) department of the center which purchased the system must be heavily involved, which can strain resources and complicate the installation and maintenance process.